Method of preparing plural gels



Patented Se t 1931' in part o sum'r EARLE H. BARCLAY,

CORPORATION, OF BALTIMORE, MARYLAND,

A .oonrba'arrou or un'rnon or PREPARING new one no Drawing. Application filed mm e1, 1929, Serial no. 401L366; aha-m amt, e, 20.1927.

lication which is a continuation application, Serial No. 185,905, filed April 22, 1927, relates .to gels comprising two or more colloidal oxides such as the oxides of aluminum or titanium and pros-- This ap losses for preparing the same.

' Hard, stable, highly porous adsorbent gels containing two or more colloidal oxides may sulphate, aluminum phate or aluminum nitrate. The alkali used the preparation of a be prepared by forming a solution containing two or more salts of metals capable of forming a metal oxide gel, and reacting such solution with an alkali. The proportions and concentrations of the solution containing the salts of two or more metals and the'alkali I employed should be such that the reaction mass is of an alkalinity just beyond neutrality, say about 0.005 N alkali. The 'metal salts which may be used in forming the solution [are titanium tetrachloride, titanium chloride, aluminum sulmay be either ammonium hydroxide, sodium hydroxide, or potassium hydroxide.

' According to the present invention, for hard, highly. porous gel comprising the oxides of both aluminum and titanium, a solution of titanium sul hate, for

v maintained at about. .2 and one to 1 ent gel comprismg titanium oxide and alum1- aluminum chloride or nitrate of may be employed in place ofthe' 10% soluexample, equal portion of a solution of aluminum sulphate of like strength. The temperature is two normal ammonium hydroxide solution is slowly added with stirring until the whole 1s slightly alkaline, that is-until the alkalinity amounts to about 0.005 N. In place of a-solution of of 10% stren h, a solution of titanium tetrachloride 0 like stre may be used. Also, a solution of a salt 0 aluminum such as tion of'aluminum sulphate;

tion." The resul The jelly so obtained is so arated from' the mother-liquor, and washe by decanta-l tin 'elly like mass is then dried at about 100 C. or a little thereabove,

and-thereafter subjectedto a higher tempera'tu for instance 150 C. to 200 C. for two or three hours.

. The washing, previouslymi;ntioried, 1119') of 10% strength, is mixe with an strength ually: and

aluminum. 7

or summons, ASSIGNOB ro m SILICA; our.

- My-products are plural metal oxide gels which are harm-stable, and highly porous,f

and capable of adsorbing water vapor to such an extent as to contain at least 21% -of its we ght (dry) of water when in equilibrium with water vapor at G. and a partial pressure of 22mm. of mercury. V g I Having thus described I the invention,

,what is claimed as new and desired to besecured by 'LettersPatent is: u

1. The process of preparing an adsorbent gel comprising titanium oxide and aluminum oxide, which comprises mim'ng titanium sulphate solution of: 10% strength with an equal portion of a solution of aluminum sulphate of 10% strength, maintaining the temperature not higher thanahout 2 below 09 6., adding slowly with stirring a one totwo normal ammonium hydroxide solution until the slim-- linity of the mixture is about 0.005 N., dry-- ing' the solid matter formed thereby and washing it at some stage of its preparation. 2. In the process ofpreparmg an adsorb after, the drying, or at two-or mo're'oi said ing difier nt proportions of titamumend num oxide, the step of treating a solution contaming atitanium salt and an aluminum salt 3. Intheprocess of preparing an adsorbent .gel com nsmg 'tamum oxide and aluminum *oxide, t e ste gradually an with thorough stirring to a solution containing a titanium salt and an aluminum salt to just beyond neutrality. j 4. In the process of preparing an a cut gel comprising titanium oxide and alumi-' ,1

num oxide, the step of. adding ammonia jgradof adding a solutiouof with thoroughstlrring to a; solutioncontaininga salt and 1 Yo a" the step of a'g lu.

minum salt to just be" ondneutrality.

tion containing a salt and an aluminum salt with alkali to just beyond neutrality and maintaining the reaction mass below- 0. C. during such treatment.

6. In the process of preparing an adsorbent gel comprising titanium oxide and aluminum oxide, the ste of adding a solution of 'alkali adually an n with thorough stirring to a so ution containing a titanium salt and 10 aluminum salt to just beyond neutrality and maintaining the reaction mass below 0 C.

durin such treatment. 7

- 7. the process of preparing an adsorbent gel comprising titanium oxide and alunimum oxide, the step of adding a sli ht excess of an ammonia solution, gradua y and with thorough stirring, to a solution'containing a titamum salt and; an aluminum salt while maintaining the reaction mass substan tially at atemperature not above 0 C.

'8. The process of prepar' adsorbent gels containing several metal oxi es, which comprises adding a solution of alkali, gradually and with thorough stirrin to a solution con- 7 tainin salts of said met while maintaining said solution at a temperature below 0 0., said alkali being added until the hydroxyl ion concentration amounts to about 0.005 N. 9. The process of preparingadsorbent gels containin several metal oxi es, which comprises ad ga solution of ammonia, gradually and with thorough stirring, to a solution containing salts of said metals, while maintaining said solution at a temperature as below 0 (3., said ammonia being added until a the hydroxyl ion concentration amounts to about 0.005 N,

10. A hard, stable, highly porous gel comprising aluminum oxide and titanium oxide, 0 and capable of adsorbing water vapor to such an extent as to contain at least 21% of its weight of water when in equilibrium with water vapor at 30 C. and a partial pressure of 22 mm. of mercury.

a In testimony whereof I hereunto aflix my signature.

w EABLE H. BARCLAY.- 

